352  PREPARATION  OF  SUCCINIC  ACID  FROM  MALATE  OF  LIME. 
sequence,  as  it  only  amounts  to  0«67  per  cent.  The  salt  thus 
obtained  is  pressed,  and  the  quantity  of  fluid  still  contained  in 
it  is  determined,  so  as  afterwards  to  calculate  its  dry  weight.  If 
the  berries  employed  be  too  ripe,  only  a  very  small  quantity  is 
obtained,  and  this  of  indifferent  quality. 
2.  The  Ferment. — The  best  ferment  was  always  putrid  caseine, 
but  it  is  not  a  matter  of  indifference  at  What  stage  of  putridity 
the  caseine  is.  Caseine  which  had  been  pressed  into  a  pot  and 
kept  for  one  and  a  half  to  two  years  covered  with  several  layers 
of  blotting-paper,  gave  the  best  results. 
3.  The  Fermentation* — -The  washed  malate  of  lime  is  stirred 
up  with  three  times  its  weight  of  cold  or  warm  water  of  about 
77Q  to  86p  F.,  in  large  stone  pots  or  tubs,  and  to  each  pound  of 
the  dry  lime  salt,  1  oz.  of  caseine  of  the  above  properties,  tritu- 
rated with  water,  is  added ;  the  vessel  is  then  placed  where  it 
will  be  exposed  to  a  temperature  varying  day  and  night  between 
51Q  and  72Q  F.  The  evolution  of  carbonic  acid  very  soon  in- 
dicates the  commencement  of  fermentation,  which  takes  place 
slowly.  If  this  goes  on  in  the  way  required  for  the  formation  of 
succinic  acid,  an  excessively  disagreeable  odor  of  rotten  cheese 
is  evolved.  If  this  disappears  at  once,  we  may  conclude  that 
other  products  are  being  formed;  if  after  once  disappearing  it 
recommences,  we  may  be  certain  of  the  formation  of  succinate  of 
lime,  although  in  this  case  a  loss  will  take  place,  which,  however, 
is  often  very  inconsiderable. 
In  from  eight  to  fourteen  days,  or  sometimes  longer,  during 
which  the  mixture  must  always  be  stirred  every  day,  the  fermen- 
tation is  complete,  and  the  succinate  of  lime  formed  is  deposited 
partly  in  fine  needles,  and  partly  united  into  crusts.  When  once 
the  formation  of  succinate  of  lime  is  completed,  the  mixture  re- 
mains without  formation  of  any  other  products  except  those 
already  mentioned,  which  are  produced  in  small  quantities  even 
for  years.  The  succinate  of  lime  thus  obtained  is  repeatedly 
washed  in  water,  and  pressed ;  a  sample  is  then  dried  upon  the 
water-bath,  so  as  to  determine  the  dry  weight  of  the  whole.  If 
it  be  in  crusts  of  too  large  size,  they  must  previously  be  broken 
up.    This  operation  stands  in  direct  relation  to  the 
4.  Preparation  of  the  Succinic  Acid. — For  the  decomposition 
of  the  succinate  of  lime,  50  parts  of  sulphuric  acid  are  employed 
